Tech Focus: Stereo 3D - Year One

It's been just over a year since Sony released its firmware upgrade for the PlayStation 3 that enabled stereoscopic 3D output on all consoles, accompanied by a range of 3D enabled titles on PSN. In the months that followed, a surprisingly large number of stereo titles were released, with the new 3DTV standard embraced not just by Sony but also by a range of third party publishers: the biggest game of the year - Call of Duty: Black Ops - supported 3D on all three major platforms.

However, as the year has progressed, there's a sense that 3D is losing momentum, that sales of 3DTVs have disappointed and that the first truly mainstream stereoscopic games machine - the Nintendo 3DS - has failed to capture the imagination of the audience. So is 3D gaming now effectively on life support? Will we continue to see the same level of impressive support for the format going forward?

There's a sense that 3D is losing momentum, that sales of 3DTVs have disappointed and that the first truly mainstream stereoscopic games machine - the Nintendo 3DS - has failed to capture the imagination of the audience

Perhaps the first question we should be addressing is exactly what 3D actually offers the gameplay experience over and above simply "looking cool". In our original interviews with the stereo 3D team at SCEE's Evolution Studios, there was talk of a more realistic, immersive presentation plus the advantages that depth perception can offer in something like a racing game.

Having played pretty much the entire catalogue of 3D titles on PlayStation 3 and Xbox 360, plus a handful of 3DS titles, it's safe to say that the majority of them sit nicely in the "looking cool" category without actually providing much in the way of enhancements to the gameplay experience. There is simply an added depth to the visuals which, by and large, results in a more pleasing visual experience but doesn't improve the way the game plays. Sometimes this can be enough - THQ's de Blob 2 has an artistic style that simply looks phenomenal in 3D - but is the stereoscopic looking actually providing any kind of gameplay premium?

There's no doubt that 3D can be much more immersive than a standard 2D look, which has an immense value in itself, but the question then moves on to the context in which the games are being played. In my experience, 3D works best when the visuals occupy the majority of the player's field of view - for the same reason that IMAX 3D is so comprehensively better than standard cinema 3D. having a "framed" 3D window in the corner of the room doesn't just reduce the impact of the 3D effect, it also limits the possibilities to game creators: it's all about generating depth, whereas the "in your face" potential of 3D that springs out of the screen is rarely explored at all. The illusion fails when the screen doesn't occupy most of your field of view.

Effects that "pop out" of the screen are generally dismissed as being gimmicks or party pieces, but it's probably the most memorable 3D effect from those that have visited the major stereoscopic movie attractions at the world's biggest theme parks. We all remember those moments where we wanted to reach out and "grab" the object that looks as though it's right in front of our eyes - there aren't many moments like that in gaming because the impact of the effect is diminished without an all-encompassing field of view. A good example of this is Super Stardust HD's amazing 3D support: the asteroids rain down on the player and the stereoscopic impact is simply phenomenal, plus the depth perception here works really well in helping you to dodge the incoming storm.

However, even with Stardust, much of the wow factor is lost if you're playing on a 32" 3DTV several feet away from the player: the immersion factor doesn't work if you're looking at a small window into a 3D world - and it's for exactly the same reason that the Nintendo 3DS doesn't quite offer all the opportunities you would want from a stereoscopic device: the screen is too small to provide anything other than a sense of depth, and in many ways even that is limited owing to the meagre 400x240 resolution.

Super Stardust HD is a good example of how improved depth perception can make a game easier to play, and there are some other decent case studies too - most notably Gran Turismo 5's stereoscopic support, which eschews exaggerated effects and camera placements in favour of a functional approach to 3D. But for the main, the notion of improved depth perception in 3D titles doesn't seem to check out: there's an improved sense of realism perhaps, but the fact is that games creators and indeed core players have pretty much mastered presenting and interpreting depth in a 2D plane. Over and above stand-out examples like Stardust, any advantage increased depth perception supplies is almost totally visual in nature - again, a "looking cool" boost only.

Questions also need to be asked about how important that boost is when other elements of a game's visual identity need to be downgraded in order to accommodate stereoscopy. The fact is that current generation consoles are being pushed to their limit and questions need to be asked about whether the Xbox 360 or the PlayStation 3 have the horsepower to provide a worthwhile 3D experience: the fact is that 3D introduces a big overhead - to provide a full 720p stereoscopic effect, fill-rate requirements double and geometry needs to be processed twice. This is why so many 3D games have resolution deficits compared to the 2D version and why frame-rates often suffer.

We even see the same thing on the Nintendo 3DS to a lesser extent, where fighting games like Super Street Fighter IV and Dead or Alive: Dimensions run at 60 frames per second in 2D, but with frame-rate halved when running in 3D. And again, we also see a lack of direction with the 3D implementation in general: a case in point is Namco-Bandai's Ridge Racer offers very little at all to players with stereoscopy engaged over the same game running in 2D, and in a game like this where the graphical impact isn't hugely impressive, you have to wonder how much better it would have looked if all the GPU power could have been concentrated into a 2D game.